The best solution seems to be plug-in hybrid cars with batteries. They move the power generation problem from cars to power plants, where nuclear, solar or some unforeseen future technology can handle it. More importantly, you can actually buy them today, and they can fall back on gasoline when exceeding the range of their batteries, so drivers don't have to worry about getting stuck like they do with all-electric cars. If the US automotive fleet were entirely converted to plug-in hybrids, then the remaining demand for gasoline would be small enough to supply with synthetic fuel, which can in principle be made carbon-neutral as well.

In the near term, plug-in hybrids with flex-fuel engines, plus lots and lots of nuclear power plants, followed by space-based solar power satellites in the medium term. Fusion in the long term (defined as "after I'm dead, dammit").